The study will test continued long-term intervention effectiveness into adolescence of very early born US preterm infants, who participated in a randomized Newborn Individualized Developmental Care and Assessment Program (NIDCAP) trial, conducted by the principal investigator, while the infants were cared for in the NICU for the first three months after their very premature births. All adolescents to be studied participated as newborns and were assigned either to control care (standard NICU care available at the time), or to experimental care (NIDCAP developmental care, with weekly bedside observations and with daily NIDCAP developmental specialist support to parents and staff), from NICU admission until 2 weeks (w) after expected full-term due date ('corrected' age [CA]).